At 22 weeks, Claire's midwife noticed a problem. It would be the start of a harrowing ordeal.

In 2015, 32-year-old Claire Cullen-Delsol was excited to learn she was pregnant with her third child.

Claire and her husband Wayne were already parents to Clara, seven, and Nathan, one, and while this pregnancy wasn’t expected, it was warmly welcomed. They were having a baby girl.

It was a sunny day in August when Claire rushed home from work to attend her 22 week scan. Her husband, mum and two kids came to the hospital with her, and waited outside while her midwife performed an ultrasound. Offhandedly, and without any sense of concern, Claire asked if everything was alright.

“No,” the midwife responded. “There are a few things I actually need to look at.”

In a diary entry from that day, Claire wrote that she moved to another room to have a second scan. This time, Wayne accompanied her, and they both sat in silence. “As the midwife scans me, I study her face for a flicker of a smile or relief. There’s none,” she wrote. As the midwife started to speak, Claire recalled how she listened “in terror, with tears running down my face.”

There were cysts on the placenta, missing bones in the baby’s face, overlapping digits, bilateral clefts, spots on the heart and issues with the baby’s brain development and kidneys.

There was talk of a chromosomal disorder, so once at home, Claire started to Google what that meant. The phrases that stuck out to her the most were, "Rarely results in live births," "Incompatible with life," and "Fatal".

Almost two weeks later, Claire and Wayne were finally given conclusive answers about their baby's condition. It was mid-afternoon on a day in late August when a midwife told Claire over the phone that her unborn baby daughter had Patau syndrome - a chromosome-based, rare genetic disorder associated with severe intellectual disability and physical abnormalities.

The following day, a doctor explained that it was expected Claire and Wayne's daughter would not be born alive. If she was, she would only live for a few hours.

For Claire, it was most likely her baby would die inside of her, and in Ireland, in 2015, her only option was to wait. Any action to induce labour would be considered a termination, and would be illegal.

In the UK, medical and surgical abortions can be carried out up to 24 weeks of pregnancy, and in exceptional circumstances, including problems with the baby's development, an abortion can be carried out after that period.

"We were told that we had to wait until the baby died, wait until I went full term, or travel to England for a termination," Claire tells SBS's Dateline on Tuesday night. But the family couldn't afford to travel to the UK, and didn't want to leave their two children behind.

"When I went out people would say things like 'congratulations', 'when are you due?', 'do you know what you're having?'" Claire tells Dateline. "I didn't want her to die, but I had no choice. She was going to die and I just needed it to be over so I could go on... so I could mourn and then so I wasn't so afraid all the time."

Continuing her pregnancy until her baby died in her womb is an experience Claire has since described as "the worst time in my life".

"I had a little routine to check if she was dead yet," Claire tells Dateline through tears.

At 26 weeks, two days after Claire's daughter Carla felt the baby kick for the first time, Claire lost her baby. On September 25, Alex Patricia Cullen-Delsol was born "beautiful, perfect, broken, and still," weighing 1lb, 10oz.

In many other parts of the world, Claire's story would likely have been different. But enshrined in the eighth amendment of the Irish constitution, since 1983, is the equal right to life of a mother and her unborn child.

Abortion in the traditionally Catholic nation, even in the case of rape, incest, child sexual abuse or foetal anomaly, is currently illegal, with a maximum penalty of 14 years in prison.

It's believed 12 women every day travel from Ireland to the UK to have an abortion, an undertaking which can cost around £1,200 altogether, or a little over $2,100 Australian dollars. A further three women each day are believed to take an abortion pill, without any medical support.

One woman who travelled abroad for a termination is Cathy*, who concealed her identity on Dateline because of the stigma against her choice in Ireland.

At six weeks pregnant, Cathy travelled to a Manchester hospital to have an abortion, and filmed part of her journey for the TV program.

While sitting in the airport on the day of her procedure, she narrates, "It's shit, yes, that I have to travel to a different country, to get what should be my right here in Ireland."

"The actual day of the abortion was numbing," she says. "I didn't even cry or get upset, because it just felt like going to the dentist. I was given a card with a number on it, in order to protect your identity. You're just a number for the day.

"It is really heartbreaking to know that you are almost being exported... that this country doesn't want to know about your problems or your issues."

On Thursday, however, voters in Ireland will have their first opportunity in 35 years to repeal this constitutional ban.

The call for a referendum gained traction in 2012, when 31-year-old Savita Halappanavar died from a septic miscarriage after being denied an abortion.

Campaigners like Claire Cullen-Delsol have added their voices to a chorus of people who argue that the decision to have an abortion is personal and private, and has no place in the constitution. Women, say the Yes campaign, "deserve to have safe, regulated abortion care in line with best medical practice so that they can be cared for and supported in their own country, by their families and doctors."

This referendum is about women like Claire and women like Cathy. Women who have "never, ever felt so rejected and alone" as when they were made to continue a pregnancy against their will, or flee to a foreign country, with no support, in order to exercise their choice.

Women who want to live in a world where their daughters, their nieces, their students, their friends, and the generation that follow them, don't have to face the same torment.

You can watch Dateline: Ireland's Abortion Debate on Tuesday 9.30pm on SBS.